Urban agriculture is a movement in transition. And it’s happening fast. Just a couple of years ago, we started hearing about Detroit’s guerrilla gardeners, reclaiming patches of vacant land in the name of fresh food, and now some of those same parcels are being assembled into large, commercially viable farming ventures. (See “Three projects that are watering Detroit’s food deserts.”) We’ve long had community gardens enriching neighborhoods, and now some architects and developers have their sights on large-scale developments centered on food production. On the zoning front, the major challenge was once just obtaining the legal right to grow vegetables and raise a chicken or two in your yard. Now some planners are pondering whole new agricultural districts within city limits.

Whenever any movement ratchets up to the next level, there’s a chance to take the message mainstream and get some powerful results. Big players who were cautiously watching the trends are now willing to put money or political capital on the table. There’s nothing wrong with seizing the moment while enthusiasm is high, but just as important is some careful and sober reflection on where it is all going. Land use is an incredibly complex arena, and no one answer is ever right in every situation. There are pitfalls to watch out for.

Strange fruit choices

Kaid Benfield, director of Smart Growth for the Natural Resources Defense Council, has long praised compact and vibrant urban neighborhoods as an antidote for chewing up more farmland on the exurban fringes. Thinking regionally, it just makes more sense to concentrate the dense network of human connections closer to the center of metro areas and to leave the natural systems in place at the edges. Benfield doesn’t hesitate to ask difficult questions about the experiments in agricultural urbanism that reverse this order.

He points to two examples on opposite sides of the spectrum — a close-in site perfectly suited for the intensive uses being proposed for agriculture, and a farmland site on the far reaches of a metropolitan area being proposed for a village — all in the name of marrying the urban and the rural.

He’s blogged about the first case, a plot of land near Logan Square in the heart of Chicago. Despite its pedestrian-oriented location on a major street, mere hundreds of feet from a Chicago El transit stop, some advocates would like to use the recently cleared land for an orchard.

Making the most of the transit system and the dense patchwork of mixed uses along the street means condensing as much human activity as possible into one place. Benfield rightly asks whether an urban farm makes the most sense in this context. “I love the idea of the orchard in concept, but its proponents may be seizing the most opportunistic space rather than the best one for their project,” he says. “My instinct is that the residents of Chicago should have their orchard, but not on a potentially busy commercial strip so close to a transit station.”

The other case is Southlands, a proposed subdivision that would add thousands of homes into an existing agricultural landscape at the very outer fringes of Vancouver’s metro area. On paper, it’s an impressively designed village nestled into farmland and open space, with the laudable goal of enhancing residents’ recognition of and participation in growing their own food. This is probably why the jury at the Congress for New Urbanism selected it for a 2010 Charter Award.

But Benfield is concerned with how this would all play out. The proposed gross density is so low that residents will inevitably fire up their car engines for the 17-mile trip into Vancouver. Extending all of the water and sewer pipes to a previously undeveloped site is also inefficient. Once the land is fragmented, it’s harder for farmers to use it effectively.

Finally, development begets development. What happens when residents start asking for a shopping center or an office park nearby? Benfield wonders whether the project, however attractively packaged, could simply be “agri-spawl.”

It’s worth noting that the Vancouver Metro government has designated the Southlands site as a Green Zone, set aside exclusively for agriculture and open space. It’s part of an urban growth boundary that has been doggedly defended since the early ’90s. There’s no getting around the fact that the development would involve a rewrite of the earlier sustainability goals.

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